Lubricant



Patented Apr. 19,1927. 1,624,939

UNITED STATES PATENT, orr cr...

STANLEY FOWLER, OF YORKSHIRE, ANT) EDWIN EDSEB, OF LONDON, ENGLAND.

v Lunmcm. No Drawing. Application filed January 25, 1927, Serial No.108,551, and in Great Britain larch 24; 1925.

- This invention comprises improvements which is soluble to a non-turbidsolution in in lubricants. The present application is theabove-mentioned proportion of benzene in parta continuation of our priorUnited at normal atmospheric temperatures has been States applicationSerial No. 104,833, filed foimd by us not to yield the aforesaid sedi-6i April 26, 1926. ment or cloudinesswhcn admixed with It has hithertobeen proposed to employ mineral-lubricating oils. -The presence of a aslubricants mixtures of lubricating oils slight amount of a transparentseparated with materials derived from the treatment colloidal body inthe benzene solution after of wool-fat and it has been emphasized thatstanding twenty-four hours may not indicate -1 0 the wool-fat employedshould be neutralized detrimental impurities provided the solution andfree of soaps. To have found, how-. is not turbid when initiallyprepared. ever. that it is not sufiicient to render the Moreoverpurified wool-fat suitable for wool-fat neutral and soap-free. Ordinaryuse according to the present invention melts neutralized cholesterolpreparations at norto a clear liquid free from turbidity if heated malatmospheric temperatures yield a sediand can be heated to 120 C. withoutfrothment when admixed with mineral hydroing at the surface. If warmedand dissolved carbons either immediately or after a time, in one half ofits weight of benzene and the whole of the wool-fat thus not going thewarm liquid mixture is shaken no froth, into permanent solution in theoil. The sedi: or at mosta quickly evane'cent froth, is pro- 75 ment ingeneral forms progressively with 'duced. Ordinary purified wool-fatyields a time and" materially diminishes the value of froth when heated,is turbid when liquefied thelubricant. A and gives turbid solutions. Ourinvestiga- We have discovered that thissediment is tions have notenabled us to state with cerdue to impurities which can be removed,tainty the precise nature of the said impurifor example by the processset forth in our ties but they may be some kind of esters,

United States Patent No. 1,610,854. This for instance cholesterolesters. process consists essentially in the steps of According to thepresent invention, therefirst neutralizing a part ofthe free fatty fore,'a lubricant is provided which consists acids in an aqueous mixture ofthe crude essentially of a neutral hydrocarbon subwool-fat by additionof alkali in quantity stantially non-volatile at normalatmosinsufiicient to efiectcom leteneutralization, pherictemperaturesadmixed with purified removing the soaps pro uced,thereafter ef-- wool-fat which is soluble to a non-turbid fectingfurther neutralization and removing solution in twice its own weig tofbenzene the soaps produced by the further neutraliat normalatmospheric temperatures. zation. The neutralization of the free fattyThe following is a description of .one exacids present in the wool-fatis therefore. ample of the preparation of a lubricant in efiected in aplurality of stages. By so doing accordance with the present invention2-- it has been found possible to prevent the for- The wool-fat is firstprepared in th anmation of emulsions containing large quantiner setforth in our United States Patent 95 40 ties of wool-fat, as well assaponified ma- No. 1,610,854.

terial. The process also causes hydrolyza- This purified-wool-fat hasthe following tion of ester's insoluble in mineral oils which partialanalysis :free fatty acid, less than are present in the wool grease bythe neutral- 0.5% (calculated as oleic acid) ash, 0.1% ization steps andthese esters are removed (representing soaps and other impurities); withthe soaps so that the product is freed water, nil.

from esters as well as fatty acids and soaps. This material dissolveswithout turbidity The product is, moreover, distinctly more in twice itsweight of benzenev and it will transparent and waxy in character thanalso be found to dissolvewcompletely' and wool-fats purified by solventextraction permanently in mineral-lubricating oils. processes.,Wherever, in the claim, urified The purified wool-fat is poured, whilewool-fat? is mentioned it is to be an erstood molten, into neutral.mineral "lubricating ,oil that the product of the above described havinga viscosity lfilufig above 400 seconds process is intended. v I Sayboltat 100 F. e temperatureof the The presence of the specified impuritiesmixture may. reach C. owingto the no can be detected b dissolvingwool-fat .in heat of the wool-fat. The amount of 011 twice its own weigt of benzene. Wool-fat may vary but may be about three or more 7 timesthe amount of wool-fat.

is a lubricant according to the present 111-- The product vention.

It is found thatif the mineral oil has a viscosity above 400 secondsSaybolt at 100 F. and is used in about the proportions stated theproduct is suitablerfor general use in internal-combustion engines orthe like. It a less liquid product is desired less mineral-oil may beused, or a thick mineral-- grease, such as petroleum jelly may be used,as a thickening agent with the mixture of wool-fat and thin oil.

The product has valuable anti-corrosive properties as more fully setforth in our co-' pending United States application Serial No. 130,100,filed August 18, 1926. Thus it has been found that the product willprevent rust on metallic surfaces to a degree beyond that capable ofbeing obtained with other known preparations. Since it has non-corrosiveproperties and will adhere tenaciously to the surface and since it isalso a good lubricant the thin layer of surface coating of this productneed not be removed when the machines having their parts coatedtherewith are put into operation but the film may be left on the parts.

It has already been pointed out hereinabove that the wool-fat employedaccording to the present invention is completely soluble in the mineralhydocarbon oil used to mix with it. One advantageous result of this factis that the wool-fat can be employed in the proportions needed to yielda lubricant of relatively high viscosity, whereas hitherto, with a viewto-reducing the tendency to sediment, the proportions of woolfat havebeen in certain cases limited to the production of these lubricatingoils of viscos'ityranging from 200 to 400 seconds Saybolt at 100 F.

\Ve claim A lubricant consisting essentially of anhydrous wool-fatcontaining less than 0.5% of fatty acids calculated as oleic acidyielding less than 0.1% of ash, capable of dissolving to a clearsolution without producing cloudiness or sediment in a minerallubricating oil, and containing such small quantities of impuritiesinsoluble in benzene at normal atmospheric temperatures as not to rendera solution of the wool-fat in twice its weight of benzine turbid, suchwoolfat being homogeneously admixed with a mineral lubricating-oilhaving a viscosity above 400 seconds Saybolt at 100 F.

In testimony whereof we afiix our signatures.

STANLEY FOWLER. EDWIN EDSER.

